1. Field of the Invention
This invention relates to plastic processing machines, and more particularly to retrofitting plasticating screw machines with bored out screw arrangements for extrusion and injection molding.
2. Prior Art
Injection molding and extrusion employs the steps of hot working a plasticized or melted thermoplastic material and forcing same under high pressure into a mold or mold space, then allowing the material to cool sufficiently so that it hardens to the extent that it can retain its shape after removal from the mold or as it emanates from the mold.
During the plasticating process, it is often desirable to add a further processed material with the plastic material being worked within a screw housing. It is further desired to be able to add a solid, such as a pellet, wire, gas or a vapor, into the actual plastic material being molded or extruded.
Limitations of present plasticating screw machinery prevent the simultaneous introduction of a gas and/or a liquid, and or a vapor, and/or a solid, into that thermoplastic material as it is going into a mold or die.
It is therefore an object of the present invention, to provide a modification to plasticating screw machines so they may have capabilities not found in the prior art.
It is a further object of the present invention, to enable a screw machine to present a solid and/or a liquid, and/or a vapor, and/or a gas, through its screw, simultaneously or sequentially into a plastic being molded and/or extruded.
It is yet a further object of the present invention, to enable a plasticating screw machine to permit the rapid cooling and completion of a plastic part in a manner not found in the prior art.
It is yet still a further object of the present invention, to provide an extrusion and/or injection molding screw with multiple capabilities to be retrofitted into a plasticating screw machine to enable it to mix and/or extrude and/or mold multiple components therewith in a manner not found in the prior art.